eesti teaduste
akadeemia kirjastus
Proceedings of the Estonian Academy of Sciences. Engineering
Periodicity of the average wind shear; pp. 65–75

Teolan Tomson, Hannu Lamp

Higher level wind speeds are traditionally predicted either on the basis of the widely used logarithmic equation or using the Hellmann equation. In both equations, a coefficient that assesses the average wind shear curvature is usually used. This coefficient has been considered to be a constant, depending on the roughness of the surrounding landscape. In this paper, on the basis of wind speeds, recorded at different heights, we show that this coefficient is not a constant but it varies periodically with a period close to one year.


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